title: Determination of three phthalate esters in environmental samples by coal cinder extraction and cyclodextrin modified micellar electrokinetic chromatography.
abstract: A new micellar electrokinetic chromatography (MEKC) method using beta-cyclodextrin (ß-CD) as the electrophoresis additive has been developed for the simultaneous determination of dimethyl phthalate (DMP), diethyl phthalate (DEP) and di(2-ethylhexyl) phthalate (DEHP) in environmental samples. To improve the sensitivity of cyclodextrin-modified MEKC (CD-MEKC), a flow injection procedure using a microcolumn packed with coal cinder as the solid-phase extractant was also investigated for the preconcentration and separation of DMP, DEP and DEHP in environmental samples. Parameters affecting CD-MEKC separation and coal cinder flow injection solid-phase extraction were systematically researched. In the presence of the running buffer [5 mmol/L of borax, 5% (v/v) methanol and 25 mmol/L of sodium dodecyl sulfate at pH 9.5], the addition of 14 mmol/L ß-CD greatly improved the separation efficiency. The analytes were quantitatively adsorbed by coal cinders and readily desorbed quantitatively with 0.2 mL of 10% (v/v) methanol-10 mmol/L disodium hydrogen phosphate. Under the optimum conditions, the enrichment factor of coal cinder was 60, and the determination limits of DMP, DEP and DEHP were 3.07, 2.07 and 4.06 ng/mL, respectively. The presented procedure was successfully applied to determine DMP, DEP and DEHP in landfill leachate and water samples with satisfactory results.
authors.affiliation: Department of Chemistry and Environmental Engineering, Hubei Key Laboratory of Pollutant Analysis and Reuse Technique, Hubei Normal University, Huangshi, P.R. China.
authors.forename: Hongli
authors.initials: H
authors.lastname: Sun
authors.affiliation: Department of Chemistry and Environmental Engineering, Hubei Key Laboratory of Pollutant Analysis and Reuse Technique, Hubei Normal University, Huangshi, P.R. China.
authors.forename: Feng
authors.initials: F
authors.lastname: Jiang
authors.affiliation: Department of Chemistry and Environmental Engineering, Hubei Key Laboratory of Pollutant Analysis and Reuse Technique, Hubei Normal University, Huangshi, P.R. China.
authors.forename: Lin
authors.initials: L
authors.lastname: Chen
authors.affiliation: Department of Chemistry and Environmental Engineering, Hubei Key Laboratory of Pollutant Analysis and Reuse Technique, Hubei Normal University, Huangshi, P.R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zheng
authors.affiliation: Department of Chemistry and Environmental Engineering, Hubei Key Laboratory of Pollutant Analysis and Reuse Technique, Hubei Normal University, Huangshi, P.R. China chemwuyiwei@163.com.
authors.forename: Yiwei
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Department of Chemistry and Environmental Engineering, Hubei Key Laboratory of Pollutant Analysis and Reuse Technique, Hubei Normal University, Huangshi, P.R. China.
authors.forename: Meilin
authors.initials: M
authors.lastname: Liu